For anyone wanting a different framerate, the fps cap works in settings.txt, e.g.
[Engine]
LimitFPS=45
I've gone with a cap of 45, which has worked well paired with frametimes of 21ms and an official charging handheld overclock of 1.2ghz / 614mhz which gets the fan going but not distractingly so as happens with higher gpu speeds. The framerate hangs around 40-45 and dips into the 30s when combat gets chaotic. A milder non-charging handheld overclock of 1.2ghz / 460mhz sees the fps around 33-38 and into the twenties with a lot of action.
Edit: on another note, I found your write-up quite confusing OP.